Limited supplies of fossil energy resources and associated global environmental damage have compelled market forces to diversify energy resources and related technologies. One such resource that has received attention is solar energy, which employs photovoltaic (PV) technology to convert light into electricity.
PV elements for converting light to electric energy are often applied as solar cells to power supplies for small power in consumer-oriented products (e.g., desktop calculators, watches, and the like). Such systems are drawing attention as to their practicality for future alternate power of fossil fuels. In general, PV elements are elements that employ the photoelectromotive force (photovoltage) of the p-n junction, the Schottky junction, or semiconductors, in which the semiconductor of silicon, or the like, absorbs light to generate photocarriers such as electrons and holes, and the photocarriers drift outside due to an internal electric field of the p-n junction part.
One common PV element employs single-crystal silicon and semiconductor processes for production. For example, a crystal growth process prepares a single crystal of silicon valency-controlled in the p-type or in the n-type, wherein such single crystal is subsequently sliced into silicon wafers to achieve desired thicknesses. Furthermore, the p-n junction can be prepared by forming layers of different conduction types, such as diffusion of a valance controller to make the conduction type opposite to that of a wafer.
In addition to consumer-oriented products, solar energy collection systems are employed for a variety of purposes such as utility interactive power systems, power supplies for remote or unmanned sites, and cellular phone switch-site power supplies, among others. An array of energy conversion modules (such as PV modules) in a solar energy collection system can have a capacity from a few kilowatts to a hundred kilowatts or more, depending upon the number of PV modules, also known as solar panels, used to form the array.
For systems that concentrate light onto a receiver with photovoltaic cells for electricity generation or heat collection, a parabolic reflector is a technique that is utilized to achieve light concentration. Parabolic reflectors, formed in one dimension or two dimensions, are sometimes manufactured by pre-shaping or molding glass, plastic, or metal into a parabolic shape, which can be expensive. An alternative method is to form semi-parabolic reflectors attached to a frame made from bent aluminum tubing or other similar structures. In these and other conventional designs, the complexity of the structure limits mass production and ease of assembly of the design into a solar collector. In many cases, a crane is needed to assemble the structures and, as such, the assembly costs are high. Likewise, alignment of the mirrors can be difficult in the field. Further, the assembly itself can be difficult to service and maintain.